Vehicle seat, especially aircraft passenger seat

ABSTRACT

In a vehicle seat, especially an aircraft passenger seat, with at least one seat component which can be adjusted in its position, such as a seat part which can be mounted with its seat frame structure ( 3 ) by way of swivelable support legs ( 7, 11 ) above a floor structure ( 1 ), the support legs ( 7, 11 ) acting on the seat frame structure ( 3 ) in pairs in the area of the front edge ( 9 ) and rear edge ( 5 ) of the seat of the seat part, and with an actuating mechanism which is connected by action to a pair of support legs ( 7, 11 ) for producing a swiveling motion of the support legs ( 7, 11 ) which causes a change in the position of the seat part, the actuating mechanism is coupled to the assigned pair of support legs ( 7, 11 ) by way of a differential mechanism ( 13 ) which converts the swiveling motion of the support legs ( 11 ) into a change of the effective length of the assigned pair of support legs ( 11 ), which length determines the vertical distance between the seat frame structure ( 3 ) and the floor structure

The invention relates to a vehicle seat, especially an aircraft passenger seat, with at least one seat component which can be adjusted in its position, such as a seat part which can be mounted with its seat frame structure by way of swivelable support legs above a floor structure, the support legs acting on the seat frame structure in pairs in the area of the front edge and rear edge of the seat of the seat part, and with an actuating mechanism which is connected by action to a pair of support legs for producing a swiveling motion of the support legs which causes a change in the position of the seat part.

Vehicle seats are known with seat components which are adjustable in their position. Thus, for example DE 101 07 197 A1 discloses a seat of the aforementioned type in the form of an aircraft passenger seat.

In vehicles for commercial conveyance of passengers, specifically in commercial aviation aircraft, it is recognized that only a limited installation space is available for seating. In other words, especially for economic reasons, an especially compact construction of the seats is desired. On the other hand, high demands can be imposed on functionality and the comfort to be afforded the seat occupant, especially in aircraft passenger seats for business class or first class. With respect to these requirements, known seats have a plurality of control, actuating and adjustment mechanisms; this results in a complex structure. In the limited space between the seat frame structure and the floor structure, very little free installation space is available. Therefore it is difficult or impossible to freely choose the geometry of the pairs of support legs and/or the geometrical locations of their coupling points to the seat frame structure and the floor structure, such that the desired change in the position of the seat part occurs when swiveling motions of the pairs of support legs are caused by the actuating mechanism.

In view of these problems, the object of the invention is to make available a vehicle seat which provides greater freedom of design in the configuration of the pairs of support legs, and at the same time adjustment of the position of the seat part in the desired manner.

As claimed in the invention this object is achieved by a vehicle seat which has the features of claim 1 in its entirety.

In that, as specified in the characterizing part of claim 1, there is a differential mechanism which changes the effective length of an assigned pair of support legs depending on their swiveling motion, which length determines the vertical distance between the seat frame structure and the floor structure, each adjustment of the position of the seat part desired can be achieved as a result of the swiveling motion of the support legs without being tied to a certain geometry of the support legs or articulated connections. In other words, in this way there is greater freedom with respect to the use of the limited free installation space which is made available, because depending on circumstances the most favorable positional arrangement of the support legs can be selected.

In a seat in which the seat part can be adjusted between an initial position which is the rear position relative to the direction of travel, and an end position which is displaced forward, by means of the differential mechanism the effective length of the support pair connected to it can be matched to the effective length of the other support pair which can be changed when the position is adjusted. Without being tied to a certain geometry of the configuration and attachment of the support legs, this ensures that the entire adjustment motion of the seat part between the initial position and the end position takes place without any change of the tilt relative to the floor structure, i.e., over the entire adjustment path a horizontal position of the seat part is maintained.

The differential mechanism can be formed by a mechanical lever mechanism.

Preferably the lever mechanism for each support leg of the assigned pair has a bell crank lever, one lever arm of which is articulated to the end of the pertinent support leg, which end is adjacent to the floor structure, and its other lever arm is articulated to the floor structure. In one preferred exemplary embodiment the two bell crank levers are permanently connected for common motion with one another by means of a shaft which extends through between the support legs from one bell crank lever to the other.

In these exemplary embodiments the actuating mechanism can have a controllable power drive which acts on the shaft, and applies an actuating force with the bell crank levers which are connected to it; this force produces a torque for the swiveling motion of the bell crank levers around their coupling point to the floor structure. The controllable power drive can be a linear drive with a driving element, for example in the manner of a piston rod, which is articulated at a distance from the axis of the shaft to a projection which extends away from the shaft.

In the exemplary embodiments in which an actuating force can be applied to the bell crank levers by means of the power drive of the actuating mechanism and causes a displacement motion of the seat part forward by way of the assigned pair of support legs, there is preferably a second power drive which acts on the shaft with an opposing actuating force in order to apply a reset force to the bell crank levers, which force seeks to produce a displacement motion of the seat part backwards. Advantageously the second power drive makes available an auxiliary force which, when the first power drive is deactivated or when the first power drive has failed, makes it possible for the seat part which has been pushed forward to be reset into the rear initial position by manual intervention without a greater expenditure of force being necessary for this purpose.

An energy accumulator, especially in the form of a pressurized spring, can be provided as the second power drive.

The invention will be described in detail below using an exemplary embodiment which is shown in the drawings, in which

FIG. 1 shows a side view of only the seat frame structure of one exemplary embodiment of the vehicle seat as claimed in the invention which has been mounted above a floor structure in the form of a aircraft passenger seat, all other means which are housed in the space underneath the seat frame and which are part of the operating system of the seat being omitted for the sake of clarity and the illustrated components being shown in the position which corresponds to the rear initial position of the seat part;

FIG. 2 shows a side view similar to FIG. 1, however, the other means which belong to the seat area and which are omitted in FIG. 1 being shown and the seat frame structure and the pair of support legs being shown in the position which is pushed forward out of the rear initial position into a middle position;

FIG. 3 shows a view corresponding to FIG. 2 in which the front end position is shown, and

FIG. 4 shows a perspective oblique view of only one connecting shaft between the bell crank levers of a differential mechanism of the exemplary embodiment, which levers are attached to the shaft on the end.

In the figures, the vehicle seat as claimed in the invention is explained using one embodiment which is an aircraft passenger seat. Of this, FIG. 1 shows only the floor structure 1 which is to be mounted above the cabin floor, the seat frame structure 3 which has been mounted above the floor structure, and the pairs of support legs which bear the seat frame structure 3, of each pair of support legs only the support leg facing die viewer being visible. The rear pair which acts on the seat frame structure 3 on its back end area 5 is an support leg 7, while the visible support leg of the front pair which acts on the front end area 9 of the seat frame structure is designated as 11. These support legs 11 are each connected to the floor structure 1 by way of a bell crank lever 13 which is articulated to the leg and which forms an articulated lengthening of the respective support leg 11, at a coupling point designated as 15. The support legs 7 of the rear pair are connected to the floor structure 1 at a coupling point 17. The opposite, top ends of the support legs 7 and 11 are coupled to the seat frame structure 3 by way of coupling points designated as 19 for the rear support legs 7 and designated as 21 for the front support legs 11.

As can readily be seen from the figures, the arms 23 and 25 of the bell crank levers 13 include an obtuse angle with one another, the arm designated as 23 forming the coupling point 15 for connection to the floor structure 1, on a shoulder 27 of the floor structure 1, which shoulder projects obliquely upward. The other, longer arm 25 of the bell crank levers 13 is connected by way of an articulation point 29 to the bottom end of the assigned support leg 11. As can readily be seen from FIG. 4, the two bell crank levers 13 are permanently connected to one another for common motion by means of a shaft 31 which extends through between the support legs 11 perpendicular to the plane of the drawing of FIGS. 1 to 3, so that in these figures only the front end 33 can be seen.

As is most clearly shown in FIG. 4, the shaft 31 between the bell crank levers 13 has a projection 35 with an end area which forms an articulation point 37 for articulated connection to the piston rod-like driving element 39 of a controllable linear drive 41. Activation of the linear drive 41 causes a retraction movement of the piston rod-like driving element 39. FIG. 1, which shows the components in the rear initial position, illustrates the position of the articulation point 37 on which the driving element 39 of the power drive 41, which is not shown in FIG. 1, acts in the position which corresponds to the fully extended position of the driving element 39. When the power drive 41 is actuated, the retraction motion of the driving element 39 causes the articulation point 37 of the projection 35 of the shaft 31 to move out of the position shown in FIG. 1 to the right; this causes rotary motion of the unit formed from the shaft 31 and the bell crank levers 13 clockwise around the coupling point 15.

FIG. 2 shows the middle position in which the driving element 39 of the linear drive 41 is partially retracted so that the bell crank levers 13 are swiveled slightly clockwise out of the position shown in FIG. 1. As a comparison of FIGS. 1 and 2 shows, the effective length of the front support legs 11, i.e., the distance between the coupling point 21 to the seat frame structure 3 and the floor structure 11, which distance is dictated by the support legs 11, is increased slightly, at the same time a displacement motion of the seat frame structure 3 forward (to the left in the drawings) having taken place, so that the rear support legs 7 have moved into a steeper position relative to FIG. 1. The increase of the effective length of the support legs 7 which results from the change of their position is equalized as a result of the aforementioned swiveling motion of the bell crank levers 13, i.e., the differential drive which is formed by the bell crank levers 13 has matched the effective length of the front support legs 11 and the rear support legs 7 to one another so that the displacement motion of the seat frame structure 3 has taken place without any tilt.

FIG. 3 shows the components in the front end position, the driving element 39 of the linear drive 41 being completely retracted, and thus the shaft 31 with the bell crank lever 13 being swiveled further clockwise around the coupling point 15. The resulting change in the position of the coupling point 29 on the arm 25 of the bell crank lever 13 causes a corresponding lengthening of the front support legs 11 for equalization of the other, in turn corresponding change of the effective length which resulted for the rear support legs 7. Thus, due to the differential mechanism the entire displacement motion of the seat frame part 3 takes place without a change in tilt.

FIGS. 2 to 4 show another shoulder 43 which is located next to the projection 35 on the shaft 31; the push rod 47 of another power drive in the form of a pressurized spring 49 is coupled to the end 45 of this shoulder. Its push rod 47 applies an actuating force to the shaft 31; this force opposes the actuating force which can be generated by the linear drive 41. The strength of this reset force or auxiliary force is chosen such that when the linear drive 41 is deactivated or has failed, the seat frame structure 3, and thus the seat part, can be pushed manually back into the rear initial position without a greater expenditure of force being necessary for this purpose.

With the vehicle seat as claimed in the invention, it is possible to ensure for several seats which are located behind one another in a row that as a result of the horizontal adjustment geometry of the seat part in the forward position it is possible to reach the rear area (seat back) of a seat or seat component, which area is located in the row in front, so that in this way the operating elements which are located there can be used, such as for example folding table units, display units and the like. As has previously been disclosed, in the first class section the seats are located at greater distances to one another in a longitudinal row, so that without the solution as claimed in the invention the assignable operating units of the preceding seat could not be used. Furthermore, it is possible, for two vehicle seats which are located immediately adjacent to one another transversely to the indicated longitudinal row, to continuously adjust the respective adjacent seat parts horizontally against one another such that a lateral offset is achieved such that seat occupants who are sitting next to one another enjoy increased freedom, especially with respect to the adjacent arm area. 

1. Vehicle seat, especially an aircraft passenger seat, with at least one seat component which can be adjusted in its position, such as a seat part which can be mounted with its seat frame structure (3) by way of swivelable support legs above a floor structure (1), the support legs (7, 11) acting on the seat frame structure (3) in pairs in the area of the front edge (9) and rear edge (5) of the seat of the seat part, and with an actuating mechanism (39, 41) which is connected by action to a pair of support legs (7, 11) for producing a swiveling motion of the support legs (7, 11) which causes a change in the position of the seat part, characterized in that the actuating mechanism is coupled to the assigned pair of support legs (7, 11) by way of a differential mechanism (13, 31) which converts the swiveling motion of the support legs (11) into a change of the effective length of the assigned pair of support legs (11), which length determines the vertical distance between the seat frame structure (3) and the floor structure (1):
 2. The vehicle seat as claimed in claim 1, wherein the seat part can be adjusted between an initial position which is the rear position relative to the direction of travel, and an end position which is displaced forward, and wherein the differential mechanism (13, 31) matches the effective length of the support pair (11) which is connected to it to the effective length of the other support pair (7) which can be changed when the position is adjusted.
 3. The vehicle seat as claimed in claim 1, wherein the differential mechanism is formed by a mechanical lever mechanism (13, 31).
 4. The vehicle seat as claimed in claim 3, wherein the lever mechanism for each support leg (11) of the assigned pair has a bell crank lever (13), one lever arm (25) of which is articulated to the end of the pertinent support leg (11), which end is adjacent to the floor structure (1), and its other lever arm (23) is articulated to the floor structure (1).
 5. The vehicle seat as claimed in claim 4, wherein the lever arms (23, 25) of the bell crank levers (13) include an obtuse angle with one another and are permanently connected to one another at a distance from their coupling points (29, 15) to the support leg (11) and to the floor structure (1) by a shaft (31) which extends through between the support legs (11) and imparts common motion to the bell crank levers (13).
 6. The vehicle seat as claimed in claim 5, wherein the actuating mechanism has a controllable power drive (41) which acts on the shaft (31) and with the bell crank levers (13) connected to it applies an actuating force which produces a torque for the swiveling motion of the bell crank levers (13) around their coupling point (15) to the floor structure (1).
 7. The vehicle seat as claimed in claim 6, wherein the power drive is a linear drive (41) with a driving element (39) which is articulated at a distance from the axis of the shaft (31) to a projection (35) which extends away from the shaft.
 8. The vehicle seat as claimed in claim 6, wherein an actuating force can be applied to the bell crank levers (13) by means of the linear drive (41) of the actuating mechanism and this force causes a displacement motion of the seat part forward by way of the assigned pair of support legs (11).
 9. The vehicle seat as claimed in claim 5, wherein a second power drive (49) acts on the shaft (31) and applies a reset force to the bell crank levers (13), which force seeks to produce motion of the pairs of support legs which causes displacement motion of the seat part backwards.
 10. The vehicle seat as claimed in claim 9, wherein there is an energy accumulator, especially a pressurized spring (49), as the second power drive. 